"I feel more frustrated having lost on penalties."
"It's worse having lost on penalty kicks."
"It's even more frustrating ~"
"I feel more frustrated having lost on penalties."
"I feel more frustrated" 「[より悔しい](https://eikaiwa.dmm.com/uknow/questions/1365/)」
"having lost on ~" 「〜で負けてしまったから」
"penalties" 「PK」"penalty kicks" も言えます。
"It's worse having lost on penalty kicks."
"it's worse" 「より悪い」・「より悔しい」
"It's even more frustrating ~" 「より悔しい」"frustrating" の代わりに "annoying" や "disappointing" もつかえます。
We lost our soccer game in penalty kicks which made the loss even more painful.
この場合、次のような言い方ができますよ。
ーWe lost our soccer game in penalty kicks which made the loss even more painful.
「サッカーの試合でPKで負けてしまったので、もっと悔しい」
to lose in penalty kicks で「PKで負ける」と言えます。
ここの悔しいは painful を使って表現すると自然で良いでしょう。
ご参考まで!